From 600620a8d50fc13f7a9cc4901b0307d09039e7bb Mon Sep 17 00:00:00 2001
From: Yves-Gwenael Bourhis <yves-gwenael.bourhis@cloudwatt.com>
Date: Fri, 20 Jan 2017 11:49:34 +0100
Subject: [PATCH] Configuring number of apache processes

By default apache spawns only one process for the wsgi app if not specified.
This patch detects the number of CPUS to configure n CPUs +1 processes by
default and allows to specify the number of processes explicitly.

Change-Id: I684ecd15193cef169d7a86f66a47b7d1d76c1c24
Closes-Bug: #1658048
---
 doc/source/topics/install.rst                        |  7 +++++++
 .../management/commands/apache_vhost.conf.template   |  2 +-
 .../management/commands/make_web_conf.py             | 12 ++++++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/doc/source/topics/install.rst b/doc/source/topics/install.rst
index 91104afe65..b3bd643508 100644
--- a/doc/source/topics/install.rst
+++ b/doc/source/topics/install.rst
@@ -104,6 +104,13 @@ Installation
 
     $ ./manage.py make_web_conf --apache --ssl --sslkey=/path/to/ssl/key --sslcert=/path/to/ssl/cert > /etc/apache2/sites-available/horizon.conf
 
+   By default the apache configuration will launch a number of apache processes
+   equal to the number of CPUs + 1 of the machine on which you launch the
+   make_web_conf command. If the target machine is not the same or if you want
+   to specify the number of processes, add the --processes option::
+
+    $ ./manage.py make_web_conf --apache --processes 10 > /etc/apache2/sites-available/horizon.conf
+
 6. Finally, enable the above configuration and restart the web server::
 
     $ sudo a2ensite horizon
diff --git a/openstack_dashboard/management/commands/apache_vhost.conf.template b/openstack_dashboard/management/commands/apache_vhost.conf.template
index 06fe27fd6d..2f299bc725 100644
--- a/openstack_dashboard/management/commands/apache_vhost.conf.template
+++ b/openstack_dashboard/management/commands/apache_vhost.conf.template
@@ -18,7 +18,7 @@
     CustomLog {{ LOGDIR }}/{{ PROJECT_NAME }}-access.log combined
 
     WSGIScriptReloading On
-    WSGIDaemonProcess {{ PROJECT_NAME }}_website
+    WSGIDaemonProcess {{ PROJECT_NAME }}_website processes={{ PROCESSES }}
     WSGIProcessGroup {{ PROJECT_NAME }}_website
     WSGIApplicationGroup {{ PROJECT_NAME }}_website
     WSGIPassAuthorization On
diff --git a/openstack_dashboard/management/commands/make_web_conf.py b/openstack_dashboard/management/commands/make_web_conf.py
index ce6bd0ea3e..2dda25d0a8 100644
--- a/openstack_dashboard/management/commands/make_web_conf.py
+++ b/openstack_dashboard/management/commands/make_web_conf.py
@@ -12,6 +12,7 @@
 
 from __future__ import print_function
 
+import multiprocessing
 import os
 import re
 import socket
@@ -74,6 +75,7 @@ context = Context({
     'SSLCERT': '/etc/pki/tls/certs/ca.crt',
     'SSLKEY': '/etc/pki/tls/private/ca.key',
     'CACERT': None,
+    'PROCESSES': multiprocessing.cpu_count() + 1,
 })
 
 context['PROJECT_ROOT'] = os.path.dirname(context['PROJECT_PATH'])
@@ -213,6 +215,14 @@ location you desire, e.g.::
                   "configuration will work only when accessed with "
                   "the proper hostname (see --hostname).")
         )
+        parser.add_argument(
+            "--processes",
+            dest="processes",
+            help=("Use with the --apache option to define the number of "
+                  "apache processes (by default the number of cpus +1 which "
+                  "is %s on this machine).") % context['PROCESSES'],
+            metavar="PROCESSES"
+        )
         parser.add_argument(
             "-p", "--project",
             dest="project",
@@ -268,6 +278,8 @@ location you desire, e.g.::
             context['CACERT'] = options['cacert']
         if options.get('logdir'):
             context['LOGDIR'] = options['logdir'].rstrip('/')
+        if options.get('processes'):
+            context['PROCESSES'] = options['processes']
         if options.get('project'):
             context['PROJECT_NAME'] = options['project']
         if options.get('hostname'):